Scleroscope



R. HERRMANN. SCLEROSCOPE.

Feb, 6, 1926.

6 SHEETS-SHEET 2.

FILED JULY 28, 1920.

Feb. 6, 1923.

H. `HERRIVIANN.

SCLEROSCOPE.

FILED Jun/2B, 1920` 6 SHEETS-SHEET 3- Feb. 6, 1923. l

` 4,444,606. R, HERRMANN. l

SCLEHOSCOPE.

, FILED JuLYza, 1920.

6 SHEETS-SHEET 6.

er 4 w.

. RICHARD HERRiifl-ANN, 01? EIEEEEIJ, GERYIANY, ASSGNR TO SCHUCHARDT & SCE-HTTE,

f2-nitrous, Gn." hier', i SCLER-J'GCFE.

Application fried July 28, i520. Serial No. 399,645.

To @Hecho/fn it maa/concern: the falling hammer through the corners oi Be it known that l, Rioininoiinninvnin a citizen of the German Empire, and resident oi Berlin9 in the State of drussim man Empire.. have invented new end use 'fui Improvements in fdcleroscopes of v the following is iuil, clear7 :ind exe t f iication.

The invention relates to a scieroscope or apparatus for testing the hardness o?? s' l 'l bodies/ more particularly metals? by nien ol a failing Weight.

it has eiready been suggested Yfor scleroscopes to guide a dropping weight or hamn mer provided with a hard point, in a giass tube provided with graduations and to return it to the top of the tube by pneumatic means into e` device tor catching and retainH ing` it. @Wing to the use oi pneumatic means, the tube had to be ciosed up, so

that its Wali between the seule marlrei o i Lfjless tube and the Weight l he outside of the t Eorined an obstacie to the enact reading the scale. Err rs in reading Were lilreiy o be caused owing to reiiection or reffiL ction Moreover the glass tube very ifragiie. The pneumatic device used for returning the weight into the catching' device `Was coin stituted in these instrunxents by n rubber ball .and tube. lt easily became leaky., and moreover, rubber cannot aivvnys be obtained of the desired quaiity. und is u comparative iy expensive materiel This invention relates u sciercffcopc in which the weight slides in o "erabiv metal guide. or return the AWeight its orignfti position a inechanica spring;- operated driver is used. it is howevern also possibie to use a pneumatica-Hy operated dev tube are preferebiv avoided.

rEhe guide truck for hammer is in the apparat the invention or prismetic shape and pret'- erably mede practically three-sided and covered in the open side with giess or seine other transparent material, owing to which it is prevented from becoming dirty. The hammer ener ges its guide only7 alon so that the enL cf surfaces i by the hummer, and air can move ii el the prism. In this Way, the height oi? rebound oie the hammer is increased bv more than 10% compared to the older devices. end therefore the sccuracv of mec-surenints` is correspondingly increhsed. The de ic returning the failing hammer to its origine? position is carried by means oi an extension through corner of the guide prism. so that the guide 'for the hammer is continuous throughout the Whoie of its length. and no iaterai deviation of the telling hammer; which would affect the accuracy. can trike place. i

The release or' the hammer and the operation of the returning device taire place perfeet-ily independentiy of each other. in that Way, when the hammer is released, the coi/ir paratively povveriul returning' spring; need not be compressed9 and the releasinqidevice can be operated by a very siight preissure ol the ifing'erT so that thereis no rist: olf forcing` the device out of its verticai position when operating it Without supports.

Moreover the returning device is so constructed that when it is opereterh the res turning pero is automaticelif,T released by stop5 ei'ter the returning` spring has been compressed by the movement ot' a spring controlled rod. After the returm the returning device. again comes into en; .{Zenient with its operating` device. i'

:in modiiied construction accordineto the invention there is moreover provided a catching device for holding` inst the 'Failing We'frht or hammer when it is about to reverse its direction oi movement in its iu von moet position. In that Way, the readingof the height ot rebound is greatly "'acilitated facilitate the reading by increasing the division of the measuring scale.

In order that the hammer may fall freely during its first downward movement, the catching device must not become operative until the hammer, after having fallen, is moving upwards, and must not interi'ere with the :said upward movement, lt has lalready been attempted to solve this prohlem by bringing the catching device which is normally in an inoperative position, into the catchingl position immediately after the rebound has taken place, by means ot an auxiliary weight ialling simultaneously with the hammer. Owing to a slightly greater heightof fall of the auxiliary weight, the setting oi the catching device in catching position takes place only when the hammer is already moving upwards. in order to ensureexact co-operation of the hammer with the auxiliary weight, the height of fall or the measuring hammer must be made very small, as otherwise there is liability to disturbances which affect the reliable maintaining ot difference in the Jfalling paths. rl`he height of rebound cannot therefore be read directly on the ham. mer, butV only with the assistance ont a separate measuring device, owing to which the apparatus becomes considerably more com. plicated and expensive than when the height of rebound can be read direct from the position of the hammer.

According to the invention, the use of the auxiliary weight is avoided, and 'the catching device is brought into the catching position directly by the Vhammer when the latter reaches its lower-most position at the nioment of rebounding, and is rendered again inoperative only when the hammer 'is returned by a suitable lifting device from the catching position to its original position. The arrangement is made so that any jamming or locking of the hammer during the last portion of its drop is avoided, and the rebound of the hammer is not hindered by the catching device. Owing to the hammer itself operating the catching device directly, exact working oi the latter is ensured in any case, so that the height of tall oi the hammer may be safely made so great that its height of rebound can be read directly on a simple scale.

Two constructions according to the invention are illustrated by way oi example in the accompanying drawings:

Figure l is a vertical longitudinal section rshowing one construction of the apparatus in the position of rest.

Figure 2 is a vertical longitudinal sect-ion through the apparatus at the moment of release of the returning device. The highest position of the returning device before it reaches the position of rest, is shown in dotted. lines.

Fi ure 3 is a cross-section on the line A l of Figure l and Figure 4 a cross-section on the line C-D of Figure 2.

Figure 5 shows a second construction of the apparatus in the normal position, in longitudinal section.

Figure 6 shows the apparatus in longitudinal section at the moment when the hammer strikes the piece to be tested.

Figure 7 shows the hammer in the catching position, in longitudinal section through the apparatus.

liigure 8 is a 'lront elevation of the apparatus, the hammer indicating the hardness 52.5. j

Figure 9 is a longitudinal section showing the apparatus when the hammer is returned to its starting position by the lifting device.

Figure l0 is a cross-section on the line E-li of Figure 5,

Figure il is a cross-section on the line G-l-l or Figure 5, and

Figures 1244 show on an enlarged scale various positions of the apparatus.

ln the constructions shown inl Figures l-Ll, in the iront of the body d oi the appaatus is arranged a prismatic, preferably three-sided guide i'or the hammer a, which is covered in iront by a stripoi glass li. The glass strip ll is arranged in a groove otl the body Z and held at the vtop and at the bottom by covering plates i6 and i6. (in the upper end oi' the body (Z is mounted a head 3l in which above the guide l() are pivoted about a pin 13 two catches or hooks b. rlhe catches are provided at the top with projections Zi and b2. rgainst the projections i is pressed by a spring le a sleeve 32 which has a hollow. conical suri'ace at the bottom.4 rlhe projections ZJ are thus moved inwards towards each other and the hoolfed bottom ends of the catches, which engage with hollow space or recess oi the hammer, are spread out (Figure l). The said sleeve 32 is surrounded by a pressure sleev 33 which is adjustably mounted in the head 3l. lt is pressed upwards by the action ot the spring 11i until its projection engages with a corresponding projection ot the bore. riChe pressure sleeve 33 has at the bottom an also hollow conical surface with which the catches engage with their lateral projections Ziz. lf the sleeve Sis pressed downwards in opposition to the action oi the spring let, its hollow conical surface will move the catches in the direction opposite to that in which they are moved by the sleeve 32, and the hooked `bottom ends of the atches are moved towards each other, until their hook-shaped ends are disengaged from the hammer so thatthe latter is released and drops (Figure 2).

in the head 31 is guided also the upper end of the rod c operating the returning dellO inea-,eee

vice. lits lower thin end engages with the groove l? in the rear part of the body d. lt is moved upwards by the spring 2d until .it strikes by inea-ns or" a coller Se against the bottom surface of elle heed 3l.

The bottoni end of the pressure rod e wliicli` is guided in the projections i8 and 182 of Vthe rear covering plaie i8 of elle epperetns, rests on a projection g et 1tlie lower end or' Elie reurnino" device 7L which e'; its ripper end is provided wili en annule-r projeetion i which loosely surrounds the rod c.

Eetween the said ennuler projection and Y.

the projecion 182 or the rear covering niet l Y is arranged V the returning spring e. ub presses the returning device npr` rds so that strikes with e cein fue 3f the upper edge 22 of the slob Q2 through which elle re'iurningdevice presses into tbe lieininer guide. ln this weg' the projeciion g ei 'tbe returning member is bold ies under 'the rod c. The projection g of the refurning ineinber is else provided with e cern fece 36, :ind further @ein face 8'? is arranged on :i projection et the botioin end of the rear coveringl plete 18.

lllie operation of lie apparatus is es Yiollows:

@n the rod c being depressed, it ecls on the projection g of ille returningr devioe and drives the leiter down7l be spring; e lferween lie projection e' and the projecifion i8? beeoinpressed. As soon es lie cern ace 3G tee progection g strikes 't-lie cern fece T these two feces slide on eecli other end the bortoni end o ilie returning); device is f'orced asideE transversely to iis direction oi? movement, and tliroufli abe slo 272 into the :1th of the liainnierJ i ntil the @rejection 23 wf loe returning device engages under alie beinrneryn and Jolie proieetion g slides of? libe lor-.fer end or ille rod c and, abus becfoi fee (Figure 2). The retur device is gli n projeoefl univerdlv7 by er-:pending e and slides along t i Tn this 9' lie whole of me `ipwerd inovei' il e reenrningoevice ne Quid of: lz'lie liemr upwerdly. As 0 ,l

lie rear liee of the glei on g engages viin the rod o,4 the lower end oi? 'be returnn device et i'irst remains in elle pesition in ieli the driver 23 projects into tbe pet-li oi' fell of lle bummer. @n tbe rod c being *eben released7 it is signin ised by the spring1 until tlie coller 24; eng); C s with the bead that wey tbe projeorion g oi jolie returning; device is releeeed by the lower end of @glie rod. c, so that the spring e forces the returning device still urtler upwards. The cern Yfece 35 slides during` liefe nieve nient on lie edge/.je 227 owing io weich r reinrning device is sent beel'; to ine "position resi' in which *olie Qrojeotion g engages under the lower end of the rod c,

to be used again.

lt w l be seen tlnnb in tins zruction 'die 'en eesilv remover fron Jlie 70 accidentally 'f'ull liter removing i n accor linea' relerence defscribed, end down in cells; tlireeieriei friet is elosed ween 1lle il. i leave lel'ween liere Y le l1ronoli wliieli elle l C tion o be seen. The `:rrr-,n part or the guide l() is closed in by e cover plaie 162. 90 Le cylindrienl rod a of abe bei trier is surrounded by e. retaining device n ucli is from niovinn in lie aldil direciiion bv recesses il? tire bof v /Z and in tbe Covering' plaie l62. This re" device 95 i Y bore.

Y herinner li preveniJ ,TQ'

flier are raised until teneonsli7 the eoni bells e515 on die lower edges of tbe traireverse bores of die bell negre )glie belle loose between tbe i ie bemin vreelj,T dem i 12? eentrirrv 'be 't enel ,i Vv down .A Y, i be conical s sleeve I fr e bemin-er re reni lie ne er a from inox" 125 ille bodv (Z zi erlindricel bore irevele en zur be pieton, 7L. oi'' :i driver tbrouf'li t nv in the body (Z3 into 'Une guiee 'l0 of the lininment.

rid eno'eges under the upper guide ldisc ader. The space below the piston 7L is connected through conduit fil-9 to a. cylinder 5G. the latter nieves an air-tight r '7-, in its position oi' rest, is ,iy a helivel sprinf'f ln vthe 5L which eloses-l t ie cylinder 50 at the ,.ioitoin, pif-.'oted about a pin le? a catch or hoolf .7 the better. hook-shzuied end ot which is moved by a fino; 33 towards the guide trzicl e hammer.

u its position of rest (Figure 5) the hama is s'znspended with its upper guide on the catching; hoolr` l). @n the lool: be depressed. it is the hes r, :ind the latthe ball cage fl?) is et iirst non. the posi fon of rest. oro the lammei' strikes the central .guide disc e strikes the and pushes it i ned or looking po- "gure lo). The rod al of the hamreduced under the central Aguide di e of." to sucl an extent theballs at this point are loose ev when the ball ooge is pullel down. and do not lock the hammer during the rest ot its downward moveoi rebound can noiv be read from the position ot its uppermost guide dise 0,2 on the Scale 12 (Figure 8).

ln order to return the hammer to its original position, the piston 5i is depressed in the cylinder 50. The air under the piston ..71 is thereby compressed and passes through conduit i-S) under the lifting piston /7 which thus moved upwards end by means of the drive 23 raises the han'iiner ci until the hook l) :nii'ain eng.. s under the upper guide disc ol the hammer a. (ln the piston 5l being :rejoin released, it is returned to its position t rest by the spring- 2e. ln thet Way a 'vimuuni is jiirodueed under the piston 7L, which, with. the cro-operation of the Weight olB the piston again moves it down, into itsv oosition of The hammer o is held fast bv the hook l) in its highest i. e. stertin@v 1 i, i am nosition. vtlhen tno hammer e is moved e miq1fJ-1iiffo3 't 1 f -1'- 4 upnios o), tic (in ei .i .i s onei cisc n, strikes the bottom face of the ball cage 43 end raises the latter again into its upper position (Figure 9).

The apparatus is then ready for use again.

The ham.-er then strikes the test u igiiieeoo The essential point always that the "atchi device should bve-brought into the l e position only by the falling harn- .f f f -4- fw'. i. J. .C .D inei tselr,V and throJ du ig the iet-nin oi ene honiniu sta fling position, it should be broi ,i in into the inopere. ive position, so 1 no longer hinders in felli n o. pneumatic returningJ device similar to thet described in the :toi-eroine may be nsefil. @it con in place ofthe Cylinder 5G and piston 51, the known pneumatic devices with rubber ball .may also be used.

TAWhat l claim is y l. `ln seleroscope: the combination with 'avity actuated hammer; of a slotted 'uide thereior. closed at the open forip ot transparent material; and o sdapted to return the hammer its starting position. the driver being` f .ed through a corner ot the grismatirv Aofuide in manner euch that a slot of said guide.. intended 'for its passage. does not eX- ih the hammer.

2. ln e, scleroscope:` the combination With e. gravity actuated hammer; of a prismetic. guide therefor7 said lguide being substantially tliree-sided.. slotted as and for the purpose set 'forth end closed at the open side by a strip ot transparent material; and a driver devine :adopted to return the hammer to its starting' position, the driver being` carried through a corner oil' the prismatic guide in manner such that a slot 01"' 'd guide'. intended for its possage. does not extend into the line o'f contact oi the guide with the hammer.

3. ln scleroscopezthe oo'mbii i f gravity actuated hammer; oi a releasing devioe therefor; and a returning' device operable independently ot said releasing device end adapted 'to positively enge-ge With the hammer to return same. l

4l. ln o. scleroscope: the combination with a gravity actueted hammer; of e device to engage the hammerftor returning same; e catching; device holding 'test the hammer in `its highest position reziched in the rebound trom a test piece; and 'mea-ns carried bythe hammer to set the eatohing` device in the downward travel or the hammer.

5. ln a scleroscope: the combination with a gravity actuated hammer; of e device to engage the hammer for returning same; catching` device holding,` test the hammer in its highest position reached inthe rebound in the construction in Figures nfl into tie line of contact of the guide i naanoo@ from a. test piece; and means carried by the han to set the catching device in the dov-inv ard travel oit the hammer; said hamnassing` tree-ijf thru the catching` device lownward travel. a scleroscope: the combination with a actuated hammer and upper and lower engaging means thereon; of a returning` device for the hammer; and acatching devi e 'for holding the hammer in its highest position reached in the rebound from the including a movable member test piece and adapted te be engaged by the upper engaging means of the hammer, as the latter reaches its lov/est position; to set said catching` de vice, the lower engaging means t ie hammer in the highest position of the said hammer engaging the said movable member to restore it to normal position.

7. ln a. scleroscope: a gravity actuated hamer having a rod portion; means for holding)` the rod in inoperative position; a releasing device therel'or; a reciprocable ball cage through -which said rod passes; balls retained thereby tor locking the rod; and means on the rod for engaging` the hall cage.

8. in a scleroscope: the combination with a gravity actuated hammer; and a releasing,r device for the hammer; ot a returning cle-- -vice; and a catching device to hold the hainmer in its highest position reached in the rehound from a test piece; and comprising reciprocable ball cage and balls Jfor holding the hammer, and a. sleeve member having inclined surfaces to cooperate With the balls in releasing;l an d locking` the hammer.

9. ln a scleroscope: a gravity actuated hammer having a rod portion of reduced thickness at its upper end, means Jfor holding` the rod in inoperative position; a releasing device therefor; a reciprocable ball cage through which said rod passes; balls retained thereby for locking said rod; and

means on said rod to set the ball cage into locking position.

l0. n a ierescope; gravity actuated hammer hat op; a rod portion; means tor holding the rod inoperative pos on; a releasing` device therefor; a reciprocable hall cage 'through which said rod passes; halls retained therein.' i'or locking; the rod; means on said rod to t the ball cage into locking position; and additional -means on the rod for restoring` the bali cage to position ot rest.

il. ,ln a scleroseope: a gravity actuated herinner having a rod portion; means for holding the rod in inoperative posit-ion; a releasing` device therefor; a reeiprocable ball cage through which the rod passes; balls retained thereby for locking the rod; and upper and lower disks on said rod upon opposite sides of the ball cage adapted to engage with same to respectively set the ball cage into locking position and to restore the same to a position of rest.

12. ln a scleroscope: the combination with a gravity actua-ted hammer; ot a pneumatic returning device for the hammer and adapted to positively engage same; and a. catching device for holding tast the hammer in its highest position reached in the rebound from a test piece.

i3. ln a seleroscope the combination with a gravity actuated hammer; of a returning device ior same and comprising` a piston havinga projection engaging the hammer1 and means tor supplying air under pressure to the piston to actuate same.

in testimony, that l" claim the `ioregoi-np?- as my invention^r l have signed my name in presence of two subseribing` Witnesses.

Witnesses:

WALTER l-liLDnenANDT. NATHAN AOKERHART. 

